The preservation of the above-identified proteinaceous foods, e.g., cheeses, crustaceans, bivalve mollusks, gastropod mollusks, fish, meats and poultry has been a major concern for humanity, and the following is a summary of the problems which have been encountered in the preservation of the above-identified proteinaceous foods.
Dating back thousands of years, before the invention of refrigeration, freezing and canning processes, various proteinaceous foods, e.g., cheeses, crustaceans, bivalve mollusks, gastropod mollusks, fish, meats and poultry, were cured by natural smoke. Historically, such proteinaceous foods have been smoked at atmospheric pressures and varying temperature ranges over long periods of time.
Smoke curing is typically done in one of two ways: namely cold-smoking; and hot smoking. The cold smoking method particularly where the proteinaceous foods products are cheeses can take up to one month depending on the cheese variety. The cold smoking process smokes proteinaceous food materials, e.g. cheese at between 4° C. to 28° C. The cold smoking method is a less stringent method and will assist in keeping proteinaceous food materials, e.g. cheese moist and acceptable.
Hot smoke can partially or completely cook, dry, and dehydrate foodstuffs and thus is not deemed to be suitable for cheeses and some other foods, by treating them at temperatures ranging from about 60° C. to about 75° C. Obviously, this should not apply to certain food categories, e.g. cheeses. Components of the smoke emitted from various types of fuel will enhance the taste and preserve the color of the food. However, it was found that smoking and cooking crustaceans, meat and poultry under pressure imparted more smoke flavor thereto tended to cause the crustaceans, meat and poultry to retain additional moisture, and caused the crustaceans, meat and poultry to be more tender as compared to meat smoked at atmospheric pressure.
Thus, with respect to cold-smoking and hot smoking, the combinations and variations in temperature from about 4° C. to about 70° C., fuel types, humidity, circulation and exposure times are great.
Historically such proteinaceous foods have been smoked at atmospheric pressures and varying temperature ranges over relatively long periods of time. It was later found that the time required to smoke such proteinaceous foods adequately could be reduced if the smoking method could be performed under pressure. It was also found that smoking such proteinaceous foods under pressure imparted more smoke flavor to the food and tended to cause such proteinaceous foods to retain additional moisture. It was then later found that the time required to smoke such proteinaceous foods adequately could be reduced if the smoking and cooking processes could be performed in combination and under pressure.
Natural smoke can preserve the nutritional components and wholesomeness of dairy products while at the same time retarding spoilage. Smoked cheese, such as smoked cheddar cheese, smoked ham and smoked turkey breast are some examples of popular foods treated by smoke.
Another method of “curing” used in less expensive cheeses is to use liquid smoke flavoring to give the cheese the outside appearance of having been smoked in the more traditional manner.
Smoked cheese is any cheese that has been specifically treated by smoke curing. It typically has a yellowish-brown outer “coating”, which is a result of this curing process. Furthermore, a common factor of the known smoking processes is that the total smoking time for cheese, smoked by method of liquid smoke, is comparatively long.
In the examples given above, the result has been a smoke-flavored food. Thus, the known processes are not completely satisfactory as regards the uniformity, the color quality and color stability and occasionally as regards their taste especially for cheeses. In many smoking methods, where separate heating surfaces are arranged in the path of the circulated treating medium (generally predominantly air), these are susceptible to contamination, wear and tear and faults.
In the field of processing of hard and soft shelled crustaceans, e.g., lobsters or crabs or shrimp, the processors have for many years used post-harvest stabilization as fresh chilled or frozen distribution methods. More typically, the processors subjected such lobsters or crabs or shrimp to methods of cooking then freezing whole and typically as frozen-in-brine packaging (e.g. known popularly in lobster processing as “popsicle pack”) or by separating the cooked meat of such lobsters or crabs or shrimp from the shell and marketing such meat of such lobsters or crabs or shrimp as frozen vacuum-pack or canned products.
These lobster or crab or shrimp processing industries are traditional in their approach and these typical processing techniques are associated with a necessity to handle unpredictable catches and large seasonal volumes of raw such lobsters or crabs or shrimp for which there is a need to stabilize such lobsters or crabs quickly and with simplicity. These approaches do not necessarily attend the changing demands of modern consumers.
In recent years, these lobster or crab or shrimp or even the oyster processing industries have responded to consumer demand for fresh lobsters or crabs or shrimp by adopting new methods of processing which include the use of the separation of the raw meat from the shells of lobsters or crabs or shrimp and subsequent rapid freezing of such separated raw meat. These new methods include the use of freeze-thaw separation techniques as well as the use of applied high hydrostatic pressure which has been shown to effect release of raw meat from the shell material of lobsters or crabs or shrimp. Extracted raw meat of lobsters or crabs is then frozen and distributed for subsequent thawing and cooking.
Heretofore, packaging of such lobsters or crabs or shrimp in buyer-friendly containers having a good visibility of such has been virtually unknown as the shells of such lobsters or crabs, by virtue of their shape and their sharp appendages, made it inappropriate to vacuum seal the lobster or crabs product in marketable packaging for retail use.
Other operators in these lobster or crab or shrimp processing industries are involved in post-harvest holding and live marketing of lobsters or crabs. These operators occupy a market niche (e.g. restaurant and supermarket trade) which is typically high priced and not available to the traditional cooked frozen product processors.
In the field of the sale of bivalve mollusks, e.g., oysters and clams and mussels and gastropod mollusks, e.g., abalone, it is known that bivalve and gastropod mollusk processors have sold freshly-caught oysters, mussels, clams and abalone, and for many years, have also utilized post-harvest stabilization of such bivalve and gastropod mollusks, by cooking such oysters, clams, mussels and abalone and have marketed the so-cooked products by fresh-chilled and frozen distribution. More typically, the mollusk processors subjected the so-cooked meat of such oysters, clams, mussels and abalone to methods of chilled shucked raw and cooked meat and individually quick frozen (e.g. known as “IQF”) techniques, or, by separating the raw or so-cooked meat of such oysters, clams, mussels and abalone from the shell and marketing such raw or so-cooked meat as chilled pack, frozen vacuum-pack or further processed canned products. These bivalve mollusk and gastropod mollusk processing industries are generally not capable of handling unpredictable catches and large seasonal volumes of raw material for which there is a need to stabilize the bivalve or gastropod mollusk product quickly and with simplicity.
In recent years, this particular bivalve mollusk processing industry has responded to consumer demand for fresh oysters by adopting new methods of processing which include the use of raw meat separation from the shell of the oysters and subsequent rapid freezing These new methods include the use of freeze-thaw separation techniques as well as the use of applied high hydrostatic pressure which has been shown to effect both contaminant microbial destruction and permit ease of raw meat release from the retaining shell material. Extracted raw oyster meat is then either sold chilled raw or frozen raw and distributed for subsequent thawing and cooking.
The preservation of fish has been a major concern for fishermen and fish processors for centuries. Originally, fish were salted and/or dried to preserve fish. Historically, fish have been smoked at atmospheric pressures and varying temperature range over long periods of time. Smoking of fish has been one of the major forms of fish preservation for centuries. Such smoking, however, can also serve to cook the fish while imparting the smoke flavor. It was later found that the time required to smoke and cook the fish adequately could be reduced if the smoking and cooking processes could be performed in combination and under pressure. It was also found that smoking and cooking fish under pressure imparted more smoke flavor to the fish and tended to cause the fish to retain additional moisture as compared to meat smoked at atmospheric pressure.
Smoking involves the burning of organic substances, such as wood, to produce a complex mix of over 400 separate chemical compounds. These compounds, when continually exposed to fish flesh, are absorbed into the fish over time and impart a smoke flavor to the fish. The smoke compounds act as a natural “bacteriostat” and greatly increase the refrigerated shelf life of the fish (up to three times the un-smoked shelf life). It is believed that smoking of fish increases the shelf life by killing a majority of the bacteria initially present, and then creating an acidic microenvironment that slows the growth of bacteria over time in refrigerated conditions. Demand for smoked fish has been significant for many years and is continuing to grow.
It is well-known that raw meat of tuna and other fish becomes oxidized in a very short time, with attendant blackening and deterioration. This oxidation proceeds even in the meat frozen at approximately −20° C., the temperature used in ordinary freezing. Therefore, such fish is usually frozen, and kept, at lower temperatures. This is the reason why the transportation and preservation of fish caught in deep-sea areas and territorial waters of foreign countries are very costly. The use of air freight, in preference to transport on ships during which stable temperature control is difficult, adds further to the transportation cost of such fish. It has long been desired to establish some inexpensive method to transport and preserve fish without diminishing or spoiling flavor in a condition similar to that attained by ordinary freezing or cold-storage.
In addition to smoking meats under pressure, it has been found that smoking and cooking meats and poultry at a pressure less than the surrounding atmospheric pressure draws moisture from the meats and poultry and helps to more quickly preserve the foods. For example, meat jerky smoked at less than atmospheric pressure cures more quickly and with a more desirable texture than does meat jerky smoked at atmospheric pressure.
Dating back thousands of years, before the invention of refrigeration, freezing and canning processes, various meats and poultry were cured by natural smoke, and it has been found advantageous to smoke meats and poultry to preserve the foods and to impart a smoke flavor to enhance taste and acceptability. Meats and poultry have been smoked by the various smoking methods as described above.
However, one of the problems inherent in smoking meat products to impart preservation properties is that the smoke odor and/or smoke taste remains present in the meat flesh. Additionally, smoke that is produced from organic fuel materials typically contains particulates, such as creosote, tar, soot, etc., which are undesirable elements to have in contact with the meats. Thus, it is beneficial to provide a smoke that has had some of the particulate removed and further remove the smoke odor/taste while still maintaining the extended shelf life. Demand for smoked meats and poultry has been significant for many years and continues to grow.
Following the invention of refrigeration, the vitality of many such proteinaceous foods have been prolonged by maintaining these proteinaceous foods in chilled storage at temperatures of about 0° C. to about 6° C. Many such proteinaceous foods in their raw state begin rapid decomposition at temperatures above about 6° C. Hence, such proteinaceous foods can be maintained fresh and unfrozen for up to two to three weeks at temperatures of about 1° C. to about 6° C. However, both endogenous and microbial-induced decomposition is inevitable and rapid after this time period and other methods of freezing, canning, and smoking have been necessary to extend the shelf-life of these proteinaceous foods.
Since the advent of mechanical refrigeration, fish have been preserved by freezing and refrigeration, thus permitting fishermen to make longer fishing trips, as well as transport the fish long distances over land or water. It was determined that the vitality of whole or filleted fish have been prolonged by maintaining the fish in chilled storage at temperatures of about 0° C. to about 6° C. Fish, in particular in its raw state, begins decomposition quickly at temperatures above about 10° C. Fish can be maintained fresh and unfrozen for up to two to three weeks at temperatures of about 0° C. to about 4° C. However, decomposition is inevitable and rapid after this time period and other methods of freezing, canning, and smoking have been found necessary to extend the shelf life of the fish.
Most unfrozen fish is considered “fresh” for as many as about 21 days from harvest. However, unfrozen fish held at refrigeration temperatures for extended periods of time usually develop high levels of bacterial contamination which can lead to decomposition. Bacterial decomposition of fish includes the cellular breakdown of the flesh of the fish due to the hydrolytic enzymes of bacteria present on or within the flesh of the fish. Conversely, frozen fish is usually frozen upon harvest which reduces the likelihood that the fish will contain significant or harmful levels of bacterial decomposition.
The length of time over which fish maintains its freshness is commonly referred to as its shelf-life. The shelf-life of fish is determined by a number of factors, including the total number of each type of bacteria initially present, the specific types of bacteria present, the temperature of the flesh of the fish and of the surrounding atmosphere, and the pH of the fish. It is known that to extend the shelf life of fish, one may, for example, reduce the number of bacteria present using chemical means, freezing or other methods, create an acidic pH and/or maintain the product below about 5° C. in its fresh state. The most common process employed to extend the shelf life of fish is freezing.
An inherent problem, however, with freezing fish is its loss of the “fresh” attributes, e.g. a “pink” or “red” meat color to both the fish flesh and the “blood line” in the fish. The loss of these attributes causes the value of the frozen fish to be less than the value of fish that has not been previously frozen. This loss of value is an interpretation of the quality of the fish by the consumer. The color of the flesh and blood line of the fish is a major factor in the selling of seafood at the consumer level. Most consumers purchase fish with their “eyes” rather than with any other factor, such as smell, taste or texture. Therefore, it is desirable to maintain the “fresh” pink/red color of the seafood products as long as possible in order to sell the product at a premium to consumers.
Non-limiting examples of patents directed to the smoking of food products include the following:
U.S. Pat. No. 4,532,858, patented Aug. 6, 1985, by Hershfeld, provided apparatus for the surface application of liquid smoke to edible articles such as a link sausage product, cheese and other meat products. The patentee also taught that a shower of liquid smoke be re-circulated and that it may be heated to an elevated level. It was thus alleged that this method resulted in a faster and more efficient smoking process.
U.S. Pat. No. 5,368,872, patented Nov. 29, 1994, by Davis et al, provided a vacuum smoker for the smoking of foods. The smoke was first concentrated by the application of pressurized air. Then, that concentrated smoke was admitted into a vacuum smoking chamber under only a partial vacuum. Once the vacuum smoking chamber became filled with smoke-filled air, the vacuum smoke transfer means was disabled and the vacuum creation means further reduced the pressure within the vacuum smoking compartment still to an undefined partial vacuum. This process was frequently repeated so that new smoke frequently refilled the vacuum smoke compartment.
U.S. Pat. No. 5,484,619, patented Jan. 16, 1996 by Yamaoka et al, provided a procedure for smoking fish and meat by extra-low temperature smoking at extra-low temperatures, e.g., between about 0° C. and about 5° C.
U.S. Pat. No. 5,910,330, patented Jun. 8, 1999, by Fessman, provided a process for smoking foodstuffs located in a treatment chamber, using a mixture of superheated steam and liquid-form smoke vapor. The smoking with the mixture of superheated steam and liquid-form smoke vapor was carried out at a pressure of from about 2 to about 10 bars.
U.S. Pat. No. 5,972,402, patented Oct. 26, 1999, by Kowalski, provided a procedure for preparing seafood or meat by first treating the seafood or meat with purified smoke in plastic bags at temperatures between its freezing point and about 7° C. The so-treated seafood or meat was then frozen.
U.S. Pat. No. 6,777,012, patented Aug. 17, 2004, by Olson, provided a procedure for the preservation of meat products by a combination of smoke, ozone and freezing procedures.
U.S. Pat. No. 6,936,293, patented Aug. 30, 2005, by Yamaoka et al, provided a procedure for processing tuna meat by injection of smoke there into, and then freezing the resulting smoked tuna at −18° C.